Datenblatt-pdf.com


AD774B Schematic ( PDF Datasheet ) - Analog Devices

Teilenummer AD774B
Beschreibung Complete 12-Bit A/D Converters
Hersteller Analog Devices
Logo Analog Devices Logo 




Gesamt 12 Seiten
AD774B Datasheet, Funktion
a
FEATURES
Complete Monolithic 12-Bit A/D Converters with
Reference, Clock, and Three-State Output Buffers
Industry Standard Pinout
High Speed Upgrades for AD574A
8- and 16-Bit Microprocessor Interface
8 s (Max) Conversion Time (AD774B)
15 s (Max) Conversion Time (AD674B)
؎5 V, ؎10 V, 0 V–10 V, 0 V–20 V Input Ranges
Commercial, Industrial, and Military Temperature
Range Grades
MIL-STD-883-Compliant Versions Available
Complete 12-Bit
A/D Converters
AD674B /AD774B
FUNCTIONAL BLOCK DIAGRAM
5V SUPPLY
VLOGIC
DATA MODE SELECT
12/8
CHIP SELECT
CS
BYTE ADDRESS/
SHORT CYCLE A0
READ/CONVERT R/C
1
2
3
4
5
CHIP ENABLE
CE 6
12V/15V SUPPLY
VCC
10V REFERENCE
REF OUT
7
8
ANALOG COMMON
AC
9
REFERENCE INPUT
REF IN
10
–12V/–15V SUPPLY
VEE 11
BIPOLAR OFFSET
BIPOFF
12
10V SPAN INPUT
10VIN 13
20V SPAN INPUT
20VIN
14
CONTROL
CLOCK
SAR 12
10V
REF
COMP
+
I DAC
MSB
N
Y
3
B
B
S
T
L
E
A
T
A
EN
Y
OB
UB
TL
PE
U
TB
199.95
k
I REF
+
DAC
N
VEE
BN
UY
FB
FB
EL
RE
S
C
LSB
VOLTAGE
DIVIDER AD674B/AD774B
28
STATUS
STS
27 DB11 (MSB)
26 DB10
25 DB9
24 DB8
23 DB7
22 DB6
21 DB5
20 DB4
19 DB3
18 DB2
17 DB1
16 DB0 (LSB)
15
DIGITAL
COMMON DC
DIGITAL
DATA
OUTPUTS
PRODUCT DESCRIPTION
The AD674B and AD774B are complete 12-bit successive-
approximation analog-to-digital converters with three-state
output buffer circuitry for direct interface to 8- and 16-bit
microprocessor busses. A high-precision voltage reference and
clock are included on chip, and the circuit requires only power
supplies and control signals for operation.
The AD674B and AD774B are pin-compatible with the indus-
try standard AD574A, but offer faster conversion time and bus-
access speed than the AD574A and lower power consumption.
The AD674B converts in 15 µs (maximum) and the AD774B
converts in 8 µs (maximum).
The monolithic design is implemented using Analog Devices’
BiMOS II process allowing high-performance bipolar analog
circuitry to be combined on the same die with digital CMOS logic.
Offset, linearity, and scaling errors are minimized by active
laser trimming of thin-film resistors.
Five different grades are available. The J and K grades are
specified for operation over the 0°C to 70°C temperature range.
The A and B grades are specified from –40°C to +85°C, the T grade
is specified from –55°C to +125°C. The J and K grades are
available in a 28-lead plastic DIP or 28-lead SOIC. All other grades
are available in a 28-lead hermetically sealed ceramic DIP.
PRODUCT HIGHLIGHTS
1. Industry Standard Pinout: The AD674B and AD774B use
the pinout established by the industry standard AD574A.
2. Analog Operation: The precision, laser-trimmed scaling and
bipolar offset resistors provide four calibrated ranges: 0 V to
10 V and 0 V to 20 V unipolar; –5 V to +5 V and –10 V to
+10 V bipolar. The AD674B and AD774B operate on +5 V
and ± 12 V or ± 15 V power supplies.
3. Flexible Digital Interface: On-chip multiple-mode three-state
output buffers and interface logic allow direct connection to
most microprocessors. The 12 bits of output data can be
read either as one 12-bit word or as two 8-bit bytes (one with
8 data bits, the other with 4 data bits and 4 trailing zeros).
4. The internal reference is trimmed to 10.00 V with 1% maxi-
mum error and 10 ppm/°C typical temperature coefficient.
The reference is available externally and can drive up to
2.0 mA beyond the requirements of the converter and bipo-
lar offset resistors.
5. The AD674B and AD774B are available in versions compli-
ant with MIL-STD-883. Refer to the Analog Devices Mili-
tary Products Databook or current AD674B/AD774B/883B
data sheet for detailed specifications.
REV. C
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties that
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2002






AD774B Datasheet, Funktion
AD674B/AD774B
PIN CONFIGURATION
VLOGIC 1
12/8 2
28 STS
27 DB11 (MSB)
CS 3
26 DB10
A0 4
R/C 5
CE 6
AD674B
OR
AD774B
25 DB9
24 DB8
23 DB7
VCC 7 TOP VIEW 22 DB6
REF OUT 8 (Not to Scale) 21 DB5
AGND 9
20 DB4
REF IN 10
19 DB3
VEE 11
BIP OFF 12
18 DB2
17 DB1
10 VIN 13
20 VIN 14
16 DB0 (LSB)
15 DGND
PIN FUNCTION DESCRIPTIONS
Symbol Pin No. Type* Name and Function
AGND
A0
9
4
BIP OFF 12
CE 6
CS 3
DB11DB8 2724
DB7DB4 2320
DB3DB0 1916
DGND
REF OUT
R/C
15
8
5
REF IN
STS
10
28
VCC
VEE
VLOGIC
10 VIN
20 VIN
12/8
7
11
1
13
14
2
P Analog Ground (Common)
DI Byte Address/Short Cycle. If a conversion is started with A0 Active LOW, a full 12-bit conversion
cycle is initiated. If A0 is Active HIGH during a convert start, a shorter 8-bit conversion cycle
results. During Read (R/C = 1) with 12/8 LOW, A0 = LOW enables the 8 most significant bits,
and A0 = HIGH enables DB3DB0 and sets DB7DB4 = 0.
AI Bipolar Offset. Connect through a 50 resistor to REF OUT for bipolar operation or to Analog
Common for unipolar operation.
DI Chip Enable. Chip Enable is Active HIGH and is used to initiate a convert or read operation.
DI Chip Select. Chip Select is Active LOW.
DO Data Bits 11 through 8. In the 12-bit format (see 12/8 and A0 pins) these pins provide the upper
4 bits of data. In the 8-bit format, they provide the upper 4 bits when A0 is LOW and are
disabled when A0 is HIGH.
DO Data Bits 7 through 4. In the 12-bit format these pins provide the middle 4 bits of data. In the
8-bit format they provide the middle 4 bits when A0 is LOW and all zeroes when A0 is HIGH.
DO Data Bits 3 through 0. In both the 12-bit and 8-bit format these pins provide the lower 4 bits of
data when A0 is HIGH; they are disabled when A0 is LOW.
P Digital Ground (Common)
AO 10 V Reference Output
DI Read/Convert. In the full control mode R/C is Active HIGH for a read operation and Active LOW
for a convert operation. In the standalone mode, the falling edge of R/C initiates a conversion.
AI Reference Input is connected through a 50 resistor to +10 V Reference for normal operation.
DO Status is Active HIGH when a conversion is in progress and goes LOW when the conversion is
completed.
P +12 V/+15 V Analog Supply
P 12 V/15 V Analog Supply
P 5 V Logic Supply
AI 10 V Span Input, 0 V to +10 V unipolar mode or 5 V to +5 V bipolar mode. When using the
20 V Span, 10 VIN should not be connected.
AI 20 V Span Input, 0 V to +20 V unipolar mode or 10 V to +10 V bipolar mode. When using the
10 V Span, 20 VIN should not be connected.
DI The 12/8 pin determines whether the digital output data is to be organized as two 8-bit words
(12/8 LOW) or a single 12-bit word (12/8 HIGH).
*Types: AI = Analog Input, AO = Analog Output, DI = Digital Input, DO = Digital Output, P = Power
–6– REV. C

6 Page









AD774B pdf, datenblatt
AD674B/AD774B
Revision History
Location
Page
Data Sheet changed from REV. B to REV. C.
Edits to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Add 28-Lead Wide Body SOIC Package Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
–12–
REV. C

12 Page





SeitenGesamt 12 Seiten
PDF Download[ AD774B Schematic.PDF ]

Link teilen




Besondere Datenblatt

TeilenummerBeschreibungHersteller
AD77403 V/5 V Low Power/ Synchronous Voltage-to-Frequency ConverterAnalog Devices
Analog Devices
AD7741Single and Multichannel/ Synchronous Voltage-to-Frequency ConvertersAnalog Devices
Analog Devices
AD7742Single and Multichannel/ Synchronous Voltage-to-Frequency ConvertersAnalog Devices
Analog Devices
AD7745(AD7745 / AD7746) 24-Bit Capacitance-to-Digital ConverterAnalog Devices
Analog Devices
AD7746(AD7745 / AD7746) 24-Bit Capacitance-to-Digital ConverterAnalog Devices
Analog Devices

TeilenummerBeschreibungHersteller
CD40175BC

Hex D-Type Flip-Flop / Quad D-Type Flip-Flop.

Fairchild Semiconductor
Fairchild Semiconductor
KTD1146

EPITAXIAL PLANAR NPN TRANSISTOR.

KEC
KEC


www.Datenblatt-PDF.com       |      2020       |      Kontakt     |      Suche